Caster



April 1, 1930.` w. G. JOHNSON l cAsTER Filed April 8, 1927 V// m r Patented Apr. 1, 1930 WILI'RED e. JOHNSON, or ELYRIA, omo,

PATENT OFFICE ASSIGNOR TOTHE COLSON COMPANY, OF

nLYnrA, onro, A oonronATIoN or Iomo cAs'rnn .Application le April .8,1 1927. Serial No. 181,992.

M invention relates to casters and .more

particularly it relates to an improved expanding mechanism for retaining a caster.V pintle within a pintle receiving socket'. l 'I An object of m invention is to provide an improved expan ing retaining mechanism for casters capable of adjust-mentwhereby it may have frictional engagement with the side walls of sockets of varying dimensions.

Another object of my invention is to provide an'improved caster retaining mechanism adaptable to securely engage the sidewalls of a socket and retain the `casterlfrom accidental disengagement therefrom and which comprises a-minimum number of parts and which isv rigid in construction whereby itis capable of withstanding the usual rough usage. .a u' Another object of my invention resides in the provision of an improved caster retain# ing mechanism which may be expeditiously inserted into and rigidly retained within a castersocket.y L g These and other objects of my invention and the invention itself will become apparent from reference to the following description of an embodiment of-my invention and in which embodiment reference will be had to the accompanying drawings forming a part 30 of the specification. I Referring 0to the drawings:

Fig.'1 isr aside elevational `view of an embdiment of 'my invention illustrating the caster socket in longitudinal medial section; Fig. 2V Vis `a vertical,'inedial sectional view of the foregoing embodiment, somel of the parts beingillustrated in elevation; lFigs. 3, Lfand 5 are: side elevational, vertical/medial,"lsectional,. and top plan views, yre- .i spectively, of an expansible element employed inthe foregoing zembodiment, Fig.:4 4' being taken'on theline4-4 of Fig. 3; and H Fig. 6 is' a fragmentary plan view of a blank prior. to forming the saineJ into the yex- Y. v pansible element.

.Referring to allv of the'figures Aof the drawings in all of which .likeparts are designated by," likrefrence characters',l vmy invention referably comprises a, caster'l ,of the type 'inoneof theembodiments of my prior application for Letters Patent entitled i Casters, Serial No. 115,279, filed June 11, 1926, comprising va caster yoke member 3, a truncated cone member v3() having a depending bolt portion 31 extending downwardly through a centrally disposed aperture 32 in the yoke and secured thereon by vvirtue of a nut 34. Said truncated cone is provided with a recessed upper surface 35 the purpose of which will hereinafter be described. 4

A plurality of anti-friction balls 36 are pro videdl and are kheld interposedV between the caster yoke top 4face and the truncated plate by means of an annularly flanged "topplate 12, the flange of which being adapted to substantially enclose the bearing balls and have two-point engagement with the same. A centrally disposed aperture is formed in the top plate 12 for the reception of a reduced end of l face of the top plate 12 and spaces the upper face of the top plate from a frustosconical expander sleeve 8 and provides a clearance whereby a wrenchmay be inserted between the caster and sleevetoengagethe portion 9 to turn the same. Said sleeve is centrally bored through which the stem vprojects and t engagesthe hexagonal portion Q'andrests upon the same-and supports the casterout of Contact with the caster support. The sleeve 8vis formed with an annular flange 26 which provides-a support upon which a hollow tubular leg 241 of ,an article Vof `furniture having Va cylindrical caster socket 23 therein, may `rest, said flange. peripheral surface is knurled tov provide a suitable anti-slip gripping portion. The sleeve 8' is also Yformed with inclined side walls-20 which may .pro- ,ject into lthe'socket 23 of the leg 24, which side walls terminatejin a flattened top 'wall 39.

ico u Threaded into the upper end of the caster stem is a second frustro-conical expander sleeve 19 having inwardly downwardly inclined side walls 21 terminating in a bottom 15 is preferably provided with integrally" formed resilient arms 111 bent upwardly and@- downwardly therefrom alternately as shown at 18 to formthe sides of .the-dislr'into` a sub-` 1 stantial hexagon in top plan view with the resilient arms 141 disposed substantially parallel each with the other toV form a resilientV expansible `skeleton-framewhic'h may be eX- panded or contracted by relativelongitudinal movement of tliesleeves towards'each other. The `free ends of: the resilient arms "14 are bent outwardly'at 18 to form impinging portions 17 which are adapt-ed toerigage the 1nner sidewalls `of thesocket. The arms engage the inclined walls of thelopposed sleeves 8 and; 1:9at the portions 18.

Theexpansibleframe is preferably formed from a blank asillustrated in Fig. 6' ofthe drawings andthe arm indicated at may be bent upwardly, the arm 4l may be bent downwardly `and the arm 42 may then be'bentupwardly and alternately and each are insequenceiuntil all; `of the arms, preferably 6 in number, have been bent upwardly or downwardly. The ends of the arms are then bent at right angles tojthe arms 14 to provide the impinging fingers 17.

A .spring 22 may be disposed "about the lower portion of the pintle 5 and compressed `between the central disk portion 15 of the frameand the-upper wall 39` of thelowermost sleeve 8 and normally tend to urge' the upwardly extending arms Yof the frame wedged between the inclined walls 21of the sleeve 19 and theinterior wall `ofS the socket 23 to'friic-4 tionally engage the fingers 17 withthe socket therebyspreventing accidental rotation `ofthe sleeve 19 on the stem 5. It is tobe understood, however, that such aspring is not essential and maybe dispensed with, if desired, I mere'- l-y employ such a spring at times wherein the caster is applied to a supporting article and which may be subjected `to undue vibrations which are apt to cause 4the sleeve 19 to accidentally rotate. j j

In applying a easter `provided with my im'- proved pintle retaining mechanism thereon, 'to a pintle'receiving socket, the stem 5, sleeves 8""and 19 and frame'13- arei-nserted into the socket andthe hexagonal portion 9"is croi tallied-by astiitalble wrench, which-in turn'ro tates Vthe pintle 5- causing the uppersleeve-LQ toimove downwardlyfon' thethreadslttowards the' `sleeveS.` A wedge action takes place be- *tweenft'he' inclined'wallfsfQ andl2l1yrespectively, of the sleeves 8 and 19 against the elbows or curved portions 18 of the arms 14 exerting a camming action thereon forcing the same outwardly and causing the fingers or impinging elements 17 to frictionally and securely engage the inner wall of the socket.` The frictional engagement between the plurality of `impinging lingers and the walls of the socket is sufficient j socket, i j

'In' order to"1'orevent rotation of the parts Awhen a wrench is first applied to turn the hexagonal portion 9, an operator may grasp the flange 26`r which is provided with the knurled surface by one hand while turning the hexagonal portion 9 with the `free hand. The peripheral :flange 26.` of the sleeve providing asupportingfwall- 24 fortheleg of the furniture relieves the expanding frame of any excess weight which might otherwise be exerted upon thesame and tilting.ofthe.stem in the socket is eliminated. 1

Having thus described my `invention in a specific embodiment, I am awarethatnumerous and extensive departuresamay be made from. the embodiment herein: illustrated and described but without departing from the spiritof my invention. i

lclaim:

tohold the caster securely in the 1. InV a caster retainer, `the combination with acasterf support having asocket, arcaster, a "pintle supported thereby telescopable into the socket, a pair of superposed laterally tapered sleeves on the pintle,the upper sleeve beingscrewlthreaded onto the pintle, with its outer tapered surface disposed so as to converge downwardly, said othersleeve disposed at the lower end of the pintle and having its outertapered surface converging upwardly,

said last named sleevey comprising a lateral flangefdisposed `exterorly ofthe support socket, said supportrestingupon said flange, an `integralresilient sheetifmetal expansible fra-meY disposed about the pintle land interposed between the sleeves, ysaid frame provided with a transversely extending intermediate-partcula iplural/ityl of resilient arms projecting upwardly vfrom the border,` of said frame 'transverseportiom and' a plurality of similar arms projecting 'downwardly therefrom, the. converging surfacesof `said sleeves engageable withsaid arms to force the arms outwardlyagainstthe inner wallsiof the support socket. when' -thestem isirotated relative to theiupper]sleeve.V j

. 2*."Coupling means `for leg `supporting swivelableL casters comprising a fcasteri stem projected upwardlyV into la le'g. socket :fromthe swivelingl mechanism fof the caster, a` perforated plate supporting the leggvsaid stem-*rotatably;` proj eeted: 3 through'` i .the perforation, said plate. supported onsthe stem, a gripping elementtcomprisng a :hubY surrounding. the stema-nda plurality'ofuresilient arms inte grally secureditoitbehub and fextendngflong.-

JID() tudinally and on different sides of the stem, and an expander for said arms adapted to be projected between their free ends, comprising a free nut, screw threaded on the stem, and a spring disposed within the socket exerting constant pressure against the hub to press the gripping element longitudinally of the stem to maintain continuous frictional engagement between the arms and the expander.

3. Coupling means for leg supporting swivelable casters comprising a caster stem projected upwardly into a leg socket from the swiveling mechanism of the caster, a perforated plate supporting the leg, said stem rotatably projected through the perforation, said plate supported on the stem, a gripping element comprising a hub surrounding the stem, and a plurality of resilient arms integrally secured to the hub and extending longitudinally and on dierent sides of the stem, and an expander for said arms adapted to be projected between their free ends, comprising a free nut, screw threaded on the stem, said gripping element being in the form of an integral spider, having a: central plate .portion constituting said hub, said arms bent substantially rectilinearly from the border portion of the hub, other resilient armsV integrally secured in like manner to alternately disposed border portions of said hub, extending longitudinally ofthe stem in the opposite direction to said iirst named arms, and expanding means supported by said plate within the socket for expanding the free ends of said last named arms against the walls of the socket.

In testimony whereof I hereunto aix my signature this 14th day of March, 1927.

VILFRED G. JOHNSON. 

